Modpack version
Enigmatica 6 0.4.13
(server issue)

Describe the bug
All vanilla mob spawners (like ones located in the nether or in dungeons) do not spawn any mobs

Logs
Input pastebin link to crash-report or latest.log, if applicable.

Screenshots
If applicable, add screenshots to help explain your problem.

Erhm, silly questions but: Is the server set to friendly difficulty, or is mob spawning off?

Erhm, silly questions but: Is the server set to friendly difficulty, or is mob spawning off?

Difficulty is set to normal, mobs in general do spawn but I'm not sure what you mean by mob spawning off.

Cool, I'll try to reproduce it then, thanks.

Here is a video I uploaded of the issue, it takes over 1 minute to spawn 1 mob at a time but i figured it should be much more (either in amount or in terms of frequency). https://www.youtube.com/watch?v=4kCPAQu7fmM

https://www.youtube.com/watch?v=4kCPAQu7fmM

Well, you haven't exactly got a lot of valid spawn spaces there with the walls and the light. This seems pretty normal to me.

i thought mob spawners for the most part override passive mob spawn rules

Ahem, got a bit ahead of myself there, sorry :P

Vanilla spawners still have spawn rules, and even though Apotheosis overrides some aspects, they still obey those criteria.

1. Hostile mobs need specific light levels
2. Passive mobs need grass to spawn on
3. Slime only spawn below a certain Y level
4. For each spawn attempt, It checks x number of random blocks in the spawn radius. If those few blocks it checks are valid spawn spaces, it'll spawn, otherwise that attempt is lost.
5. Only X mobs of the same type are allowed in the spawn area before it stops spawning. These can easily be out of sight in those dungeons, behind walls, etc.

A spawner that only has a 5x5x5 area of air blocks to attempt to spawn in will spawn far fewer mobs than a spawner with the full area open. Any light sources will diminish or even halt spawning by reducing the number of valid spawnable areas.

As a test, take the spawners out (move them with silk touch or a cardboard box) and place them in a nice 11x7x11 open area with no light. How to they behave there?